Windows代码,添加一个节,以及RVA跟FOA互相转化,以及内存文件对齐代码.

/*
1.修改文件头节个数 +1
2.修改ImageBase
3.遍历节表,拷贝最后一个节表到下面
4.修改节的虚拟大小(节表.virtualSize)
5.修改节的虚拟地址(RVA 节表.virtualAddress) 内存对齐( 上一个节表.virtualAddress + 上一个节表.virtualSize);
6.修改节的文件偏移位置,以及文件大小
*/

/*
函数作用: RVA转化为FOA
参数: 传入RVA虚拟地址的值,返回FOA文件偏移.
内部使用: g_szBuffer是文件映射的首地址.
*/


DWORD RetRvaToFoA(DWORD RvaValue)
{
	int RetRvaValue = 0;
	if (RvaValue > pOptHead->ImageBase)
	{
		RetRvaValue = RvaValue - pOptHead->ImageBase;
	}

	//定位节表位置,遍历节表.判断是否在节表内.
	PIMAGE_DOS_HEADER pDosHead = (PIMAGE_DOS_HEADER)(g_szBuffer);  //g_szBuffer是文件映射的首地址.
	PIMAGE_NT_HEADERS pNtHead = (PIMAGE_NT_HEADERS)((DWORD)g_szBuffer + pDosHead->e_lfanew);
	//定位节表.
	PIMAGE_SECTION_HEADER SectionTableAddress = IMAGE_FIRST_SECTION(pNtHead);//获得了节表的首地址
	for (int i = 0; i < pNtHead->FileHeader.NumberOfSections; i++)
	{
		if (RetRvaValue >= SectionTableAddress[i].VirtualAddress  &&
			RetRvaValue < (SectionTableAddress[i].VirtualAddress + SectionTableAddress[i].SizeOfRawData))
		{
			//落在这个节中.
			RetRvaValue = RetRvaValue - SectionTableAddress[i].VirtualAddress; // 文件偏移 -文件偏移首地址 = 偏移. 偏移加上自己的VirtuallAddress 就是在内存中的RVA
			RetRvaValue = RetRvaValue + SectionTableAddress[i].PointerToRawData;
			break;
		}
	}
	return RetRvaValue; //返回FOA在内存中的RVA偏移.
}

/*
函数作用: 填写FOA值,转换为RVA
*/

DWORD RetFoAtoRva(DWORD FoAvalue)
{
	int RetFoaValue = 0;
	//定位节表位置,遍历节表.判断是否在节表内.
	PIMAGE_DOS_HEADER pDosHead = (PIMAGE_DOS_HEADER)(g_szBuffer);
	PIMAGE_NT_HEADERS pNtHead = (PIMAGE_NT_HEADERS)((DWORD)g_szBuffer + pDosHead->e_lfanew);
	//定位节表.
	PIMAGE_SECTION_HEADER SectionTableAddress = IMAGE_FIRST_SECTION(pNtHead);//获得了节表的首地址
	for (int i = 0; i < pNtHead->FileHeader.NumberOfSections; i++)
	{
		if (FoAvalue >= SectionTableAddress[i].PointerToRawData && FoAvalue < (SectionTableAddress[i].PointerToRawData + SectionTableAddress[i].SizeOfRawData))
		{
			//落在这个节中.
			RetFoaValue = FoAvalue - SectionTableAddress[i].PointerToRawData; // 文件偏移 -文件偏移首地址 = 偏移. 偏移加上自己的VirtuallAddress 就是在内存中的RVA
			RetFoaValue = RetFoaValue + SectionTableAddress[i].VirtualAddress;
			break;
		}
	}
	return RetFoaValue; //返回FOA在内存中的RVA偏移.
}

// 按照内存对齐,以及文件对齐. 第一种方式

//传入PE的原始内存对齐值,然后传入你的要进行对齐的值.  
例子:

RetSectionAlignment(pOptHead.FileAlignment, pSection.virtualsize + pSection.virtualAddress);//返回节表虚拟大小+虚拟地址,按照内存对齐之后的值.

int RetSectionAlignment(DWORD Alignment, DWORD sizeOfImage)
{
	//if (Alignment <=0)
	//{
	//    AfxMessageBox(_T("计算内存对其值出错.请检查"));
	//    return 0;
	//}
	//while ((sizeOfImage %  Alignment) != 0) //当不等于0就说明不是对齐.
	//{
	//   
	//    sizeOfImage = sizeOfImage + 0x1000;
	//}
	int ret = 0;
	int result = 0;
	result = sizeOfImage % Alignment;
	if (0 != result)
	{
		ret = ((sizeOfImage / Alignment) + 1) * Alignment;
	}
	else
	{
		ret = sizeOfImage;
	}

	return ret;
}

int RetFileAlignment(DWORD Alignment, DWORD Value)
{
	if (Alignment <= 0)
	{
		OutputDebugString(TEXT("计算文件对其值出错.请检查"));
		return 0;
	}
	//while ((Value %  Alignment) != 0) //当不等于0就说明不是对齐.
	//{

	//    Value = Value + Alignment;
	//}
	//return Value;

	int ret = 0;
	int result = 0;
	result = Value % Alignment;
	if (0 != result)
	{
		ret = ((Value / Alignment) + 1) * Alignment;
	}
	else
	{
		ret = Value;
	}

	return ret;

}


原文地址:https://www.cnblogs.com/iBinary/p/10749313.html